This invention relates to improvements in an arc welding robot control system employing the so-called point-to-point teaching, computer controlled playback system in which there are stored a plurality of points and a robot is automatically moved to pass through the stored points one after another for automatically effecting the arc welding.
A conventional arc welding robot control system has comprised an arc welding robot including the main body provided at the extremity with a welding torch, a control console and a teaching box. The teaching box has taught a plurality of points through which the welding torch passes successively on the particular workpiece and the attitude of the welding torch relative to the workpiece at each of the taught points one after another. The control console has included a central control unit in which the taught points and attitude of the welding torch are stored along with the welding conditions such as a welding voltage, a welding current etc. in one section defined by each pair of adjacent taught points, those welding conditions being set by a key board disposed in the control console and displayed on a cathode ray tube also disposed in the latter. The control console has been connected to the main robot body and a welding electric source which is, in turn connected to both a feed reel for feeding a welding wire to the welding torch and the workpiece. The welding torch has responded to command signals from the central control unit in the control console to successively pass through the taught points to effect the arc welding on the workpiece.
There have been recently developed welding electric sources of the type enabled to selectively carry out a plurality of types welding process, for example, the pulsed and short arc welding processes only through the operation of a switching element disposed therein.
Also workpieces have increased each of which includes portions having different weld quality or which require complicated welding attitudes. The welding of those workpieces gives the better result by changing one to the other of the pulsed and short welding processes as required.
However conventional arc welding robot control systems such as described above have been unable to specify the types of welding process resulting in the disadvantage that the welding is forcibly effected according to an unsuitable one of the types of welding process, alternatively, that the particular welding is divided into two steps each of which is executed according to that type of welding process suited thereto.
Accordingly it is an object of the present invention to provide a new and improved arc welding robot control system including means for selecting the types of welding process by a teaching box or a key board disposed therein whereby the automatic arc welding is continuously effected according to that type of welding process most suitable for each of portions into which an associated workpiece is divided in order to specify the types of welding process to those portions.